Maine PUC Net Energy Billing (NEB) Programs and Credit Mechanisms

The Maine Public Utilities Commission (PUC) oversees Net Energy Billing (NEB) programs, which allow customers who generate their own electricity, typically through solar panels, to receive credit for excess power sent back to the grid. These programs are defined by Title 35-A, Sections 3209-A and 3209-B of the Maine Revised Statutes. Understanding these regulations is crucial for residential, commercial, and institutional customers considering solar energy in Maine.

Maine's Net Energy Billing Framework

Maine's NEB framework provides two primary programs: the general Net Energy Billing program under §3209-A and a specific Commercial and Institutional Net Energy Billing program under §3209-B. Both programs outline system size limitations, credit mechanisms, and consumer protections.

General Net Energy Billing (§3209-A)

This program applies to residential, commercial, and institutional customers. It defines net energy billing as a practice where a customer is billed based on the difference between the kilowatt-hours delivered by the utility to the customer and the kilowatt-hours delivered by the customer to the utility over a billing period. This calculation takes into account accumulated unused kilowatt-hour credits from the previous billing period.

Key features of the general NEB program:

• System Size Limit: Your distributed generation resource must be less than 5 megawatts. For municipalities, systems can be 5 megawatts or more, provided that less than 5 megawatts is used for NEB.
• Customer Types: This program is available to residential, commercial, and institutional customers.
• Shared Financial Interest: Multiple customers of an investor-owned transmission and distribution utility may share a financial interest in a distributed generation resource. This is limited to 10 eligible customers or meters for resources in northern Maine, unless the utility's billing system can accommodate more.
• Credit Mechanism: Billing is based on the net difference of kilowatt-hours exchanged with the grid, considering accumulated unused kilowatt-hour credits.
• Credit Rollover and Expiration: Accumulated unused kilowatt-hour credits from the previous billing period are carried forward. However, unused credits expire periodically. The value of all unused kilowatt-hour credits that accumulated and expired during the prior calendar year must be remitted on or before April 1st of each year to the administrators of the statewide low-income assistance plan and individual low-income assistance programs.
• Agreement Entry Limitation: After December 31, 2025, the commission may not allow a transmission and distribution utility to enter into a net energy billing agreement with a distributed generation resource that is interconnected or planned to be interconnected to the distribution grid on the utility side of a customer's utility meter.
• Billing Term Length: An amendment, revision, or reissuance of a net energy billing agreement made after June 1, 2025, may not include a delivery period end date that is later than the end date provided for in the agreement that is subject to the amendment, revision, or reissuance.

Commercial and Institutional Net Energy Billing (§3209-B)

This program is specifically designed for nonresidential customers of investor-owned utilities. It also uses a net energy billing system, but with distinct rules for credit mechanisms, duration, and tariff rates.

Key features of the Commercial and Institutional NEB program:

• System Size Limit: Your distributed generation resource must be less than 5 megawatts.
• Customer Types: This program is for nonresidential customers of investor-owned utilities.
• Shared Financial Interest: Multiple commercial or institutional customers may share a financial interest. This is limited to 10 customers or meters for resources in northern Maine, unless the utility's billing system can accommodate more.
• Credit Mechanism: This refers to the system of bill credits available under the program.
• Credit Rollover: Credits that remain unused at the end of any billing period may be carried forward for up to one year from the end of that billing period.
• Credit Duration: The credit duration for projects under this program is no less than 20 years from the date of first receiving the credit.
• Collocation and Subscription Requirements (from 12/31/2023): A distributed generation resource may be used for net energy billing under this section only if the distributed generation resource is collocated with all of the distributed generation resource's net energy billing customers, and those customers are subscribed to 100% of the facility's output under this section. This rule does not apply to agreements executed on or before December 31, 2023.

Tariff Rates for Commercial and Institutional NEB

The tariff rates for Commercial and Institutional NEB projects vary based on the system size and the date the rates apply. The Maine PUC is responsible for publishing these tariff rates on its publicly accessible website.

For resources greater than 1 megawatt (until December 31, 2025): The tariff rate will equal the standard-offer service rate established under section 3212 that is applicable to the customer receiving the credit, plus 75% of the effective transmission and distribution rate for the rate class that includes the smallest commercial customers of the investor-owned transmission and distribution utility. This rate applies if the entity commenced on-site physical work before September 1, 2022, or if the resource is collocated with customers subscribed to at least 50% of its output.

For resources 1 megawatt or less (until December 31, 2025): The tariff rate will equal the standard-offer service rate established under section 3212 that is applicable to the customer receiving the credit, plus 75% of the effective transmission and distribution rate for the rate class that includes the smallest commercial customers of the investor-owned transmission and distribution utility.

For resources not governed by paragraph A (2022): The tariff rate will equal the standard-offer service rate established pursuant to section 3212 that was applicable to the rate class of the customer receiving the credit on December 31, 2020, plus 75% of the effective transmission and distribution rate that was in effect on December 31, 2020, for the rate class that includes the smallest commercial customers of the investor-owned transmission and distribution utility.

For resources not governed by paragraph A (from January 1, 2023): The tariff rate will increase by 2.25% on January 1st of each subsequent year, beginning January 1, 2023.

For resources 3 megawatts to less than 5 megawatts (from January 1, 2026): The tariff rate will equal the tariff rate calculated under paragraph A-1 applicable in 2026. This rate will then increase by 2.25% on January 1st of each year, beginning January 1, 2027.

For resources less than 3 megawatts (from January 1, 2026): The tariff rate will equal the tariff rate established by the commission pursuant to paragraph A that was applicable in 2025 to the rate class of the customer receiving the credit. This rate will then increase by 2.25% on January 1st of each year, beginning January 1, 2027.

Consumer Protection and Enforcement

The Maine PUC emphasizes consumer protection within its NEB programs. Project sponsors must obtain explicit affirmative authorization from customers and provide residential customers with a standard disclosure form. Customers have the right to rescind an agreement within 5 days of receiving their first bill. Sponsors may not collect unreasonable costs from defaulting customers, must comply with commission standards, and cannot release personal information without explicit consent. Compliance with the Maine Unfair Trade Practices Act and federal Equal Credit Opportunity Act, as well as telemarketing laws, is also required.

The Commission has the authority to apply to the Superior Court to enforce orders related to consumer protection. It may impose administrative penalties and order restitution. Violations related to information release or telemarketing are reported to the Attorney General, and any violation of consumer protection is considered a violation of the Maine Unfair Trade Practices Act.